Some good and bad news for customers eagerly awaiting the delivery of their Oculus Rift virtual reality headsets: A parts shortage is delaying the delivery of some headsets, but Facebook-owned Oculus will pick up the bill for shipping.

Word of the delay first came by way of a tweet posted Saturday morning by CEO Brendan Iribe: “First set of Rifts are going out slower than we orig estimated, so we’re giving free shipping for all pre-orders,” he wrote, later adding that the free shipping applies to all preorders made before midnight PT on April 1. In an email sent Saturday to affected customers, the company pointed to “an unexpected component shortage” as the culprit for the delay and promised to give customers an updated shipping date on April 12.

First set of Rifts are going out slower than we orig estimated, so we're giving free shipping for all pre-orders, including international.

— Brendan Iribe (@brendaniribe) April 2, 2016

The $599 headsets started shipping March 28 to less than enthusiastic reviews. That marked the unofficial start of a new generation of technology promising to transport people into new worlds. HTC’s Vive VR headset is set to start shipping on April 5, which means Oculus won’t be first out of the gate for some customers. Oculus did not immediately respond to a request for more details about the delay.